How does the 2025 acute coronary syndrome (ACS) guideline change the practice for emergency physicians managing patients with ACS, including those with ST-elevation myocardial infarction (STEMI), non-ST-elevation myocardial infarction (NSTEMI), or unstable angina?

KEY CHANGES IN THE 2025 ACS GUIDELINE FOR EMERGENCY PHYSICIANS

The 2025 ACC/AHA/ACEP/NAEMSP/SCAI guideline for acute coronary syndrome management introduces several critical changes that significantly impact emergency physician practice, particularly emphasizing rapid diagnosis, streamlined reperfusion pathways, and updated treatment strategies. 1

Prehospital and Initial Assessment Changes

• 12-lead ECG acquisition and interpretation within 10 minutes of first medical contact (FMC) is now a Class I recommendation to rapidly identify STEMI patients 1
• Prehospital ECG transmission to PCI centers while en route is emphasized to expedite coronary reperfusion upon arrival
• High-sensitivity troponin (hs-cTn) assays are now preferred with shorter repeat measurement intervals (1-2 hours for hs-cTn vs. 3-6 hours for conventional assays) 1, 2

Reperfusion Strategy Updates

• Goal FMC-to-device time remains ≤90 minutes for direct presenters and ≤120 minutes for transfers 1
• Complete revascularization strategy is now recommended for both STEMI and NSTE-ACS patients, with preference toward performing multivessel PCI in a single procedure rather than staged procedures 1
• For STEMI patients where PPCI is not feasible within 120 minutes of FMC, fibrinolysis should be administered within 30 minutes (door-to-lysis time) 1, 3

Cardiogenic Shock Management

• Emergency revascularization of the culprit vessel by PCI or CABG is indicated for ACS with cardiogenic shock regardless of time from symptom onset (Class I, B-R) 1
• Routine PCI of non-infarct-related arteries at the time of PPCI is now contraindicated in cardiogenic shock due to higher risk of death and renal failure (Class III: Harm) 1
• Microaxial intravascular flow pump use is reasonable (Class IIa) in selected patients with STEMI and severe/refractory cardiogenic shock to reduce mortality 1
• Routine use of intra-aortic balloon pump (IABP) or VA-ECMO is not recommended (Class III: No Benefit) due to lack of survival benefit 1

Antiplatelet Therapy Changes

• Dual antiplatelet therapy (DAPT) with aspirin and a P2Y12 inhibitor remains indicated for at least 12 months as the default strategy in patients not at high bleeding risk 1, 2
• Ticagrelor or prasugrel is now recommended over clopidogrel for ACS patients undergoing PCI 1, 4, 5
• New bleeding risk reduction strategies are emphasized:
  • Proton pump inhibitor for patients at risk of GI bleeding
  • Transition to ticagrelor monotherapy ≥1 month after PCI if DAPT has been well-tolerated
  • For patients requiring long-term anticoagulation, aspirin discontinuation 1-4 weeks after PCI with continued P2Y12 inhibitor (preferably clopidogrel) 1

Procedural Strategy Updates

• Radial approach is now preferred over femoral approach for PCI in ACS patients to reduce bleeding, vascular complications, and death 1
• Intracoronary imaging is now recommended to guide PCI in ACS patients with complex coronary lesions 1
• For NSTE-ACS patients, timing of invasive strategy should be based on risk:
  • Immediate (<2h) for very high-risk patients
  • Early (<24h) for high-risk patients
  • Within 72h for intermediate-risk patients 1, 2

Post-Discharge Care

• Red blood cell transfusion to maintain hemoglobin of 10 g/dL may be reasonable in ACS patients with acute or chronic anemia who are not actively bleeding 1
• Fasting lipid panel is recommended 4-8 weeks after initiating or adjusting lipid-lowering therapy 1
• Home-based cardiac rehabilitation is now recognized as an option for patients unable or unwilling to attend in-person programs 1

Common Pitfalls to Avoid

• Delaying ECG acquisition beyond 10 minutes of FMC can significantly delay recognition of STEMI and time to reperfusion
• Missing posterior STEMI - ST-segment depression in anteroseptal leads (V1-V3) could indicate posterior STEMI and warrants posterior lead ECG 1
• Routine PCI of non-culprit vessels in cardiogenic shock is now considered harmful and should be avoided 1
• Using clopidogrel as first-line P2Y12 inhibitor when prasugrel or ticagrelor can be used (consider bleeding risk and contraindications) 1, 4, 5
• Using prasugrel in patients with history of TIA/stroke (contraindicated) or those ≥75 years (generally not recommended) 4

The 2025 ACS guideline represents a significant evolution in emergency care for ACS patients, emphasizing rapid diagnosis, streamlined reperfusion pathways, and updated pharmacological strategies to improve mortality and morbidity outcomes.